Optical filters based on polymer asymmetric bragg couplers and its method of fabrication

Abstract

The present invention discloses a method for fabricating an optical filter based on polymer asymmetric bragg couplers using holographic interference techniques, soft lithography, and micro molding, which comprises following steps: prepare a UV polymer with gratings; coating photo-resister film on the UV polymer, and exposed by UV light to obtain a photo-resister mold with two grooves each having gratings; coating diluted PDMS film on the photo-resister mold, and baking the PDMS film to obtain a PDMS mold having two waveguides with gratings; placing glass substrate over the PDMS mold to form a first tunnel; injecting a precure UV polymer into the first tunnel to from a cladding layer with two grooves having gratings pattern at its bottom; placing glass slide over the cladding layer and injecting a mixed UV polymer into the grooves to form waveguide cores; placing a second glass substrate over the cladding layer, and injecting UV polymer to form an upper cladding layer laminated with the cladding layer to obtain the optical filter based on polymer asymmetric bragg couplers.

Description

FIELD OF THE INVENTION[0001]The present invention relates to a method for fabricating optical filter based on polymer asymmetric bragg couplers, especially to a technique that combines the holographic interferometry, soft lithography and micro-molding processes to rapidly produce submicron range gratings on the waveguides of the optical filter based on polymer asymmetric bragg couplers.BACKGROUND OF THE INVENTION[0002]Wavelength division multiplexing (WDM) has proven to be a key technology for accommodating large bandwidths for the global spread of multimedia communications in optical fiber networks. In WDM-based networks, optical add / drop multiplexer (OADM) devices used to insert (add) or extract (drop) a specific wavelength in optical fiber communication systems are essential. These components allow the extraction of a wavelength from a transmission loop and the addition of the same wavelength to the network (Reference: T. Erdogan, “Optical add-drop multiplexer based on an asymmet...

AI Technical Summary

Benefits of technology

[0007]Another object of the present invention is to develop a process to fabricate dual-channel polymeric waveguide filters based on an asymmetric Bragg coupler (ABC) whose difference of effective refractive indices of two single waveguides is easily controlled to avoid the unwanted overlap of the transmission spectrum.

Problems solved by technology

However, their performance is extremely sensitive to the balance of the interferometer and relative placement of the two gratings; therefore, some post-fabrication trimming is often necessary.

The main drawback of such a device is that when it operates in a small spectral bandwidth, a long interaction grating length (about a few hundreds of grating periods) is required.

Therefore, it is not beneficial for device integration.

However, the need for non-reciprocal optical circulators limits its application in integrated optical formats.

Therefore, when the effective index of any individual waveguide was changed it results in a shift in the center wavelength.

Images